For decades, the image of Paranthropus boisei has been dominated by his skull. His robust jaw, enormous molars and a prominent sagittal crest on the head to anchor powerful muscles, chewers defined him as the “Nutcracker Man”, a specialized hominid on a diet of hard, fibrous vegetables. But a fundamental part of your biology, your hands, It was still a complete mystery.a key missing piece in the puzzle of human evolution. Until now.
The discovery. The study published in Nature presents the discovery that changes the rules with which we were playing: the first hand and foot bones unambiguously associated with a Paranthropus boisei.
These fossils are not new, but were discovered between 2019 and 2021 on the shores of Lake Turkana, in Kenya, and have an estimated age of just over 1.52 million years. Now, in addition to completing the skeleton of this ancient relative, it also completely redefines what we thought we knew about its capabilities.
A tooth as a key. The team of paleoanthropologists, led by Carrie S. Mongle of Stony Brook University, found the remains after a researcher detected the sheen of tooth enamel on the surface. When excavating, a finger bone appeared so large that they doubted whether it belonged to a hominid. The unequivocal association of the bones of the hand with dental and cranial remains diagnostic of P. boisei It was the key that confirmed the identity of the fossil.
“In some ways, it was surprising how many aspects of this hand were similar to ours,” Mongle says. The analysis reveals a fascinating combination of features that until now had not been considered in this case. On the one hand, the hand of KNM-ER 101000 It had intrinsic proportions similar to those of modern humans: a long and robust thumb in relation to the other fingers to be able to act as a pincer.
This anatomy would have allowed him to make precision grips, opposing the pads of the fingers with that of the thumb, a fundamental skill for complex manipulation. And this is something that today is really important for us as humans, trying to preserve this movement at all times when there is a problem with our hands.
The uses they gave it. In this case, the hand also shows great extraordinary robustness and characteristics that remind us many of those we see in gorillas. Something especially present in the region of the little finger and also the palm.
And this is where the key to this research comes: the researchers suggest that this morphology was not just for climbing, although it would facilitate a powerful grip for this. In fact, the curvature of the phalanges is less than that of other climbing hominids, indicating that it was not their main mode of locomotion.
The main hypothesis is that these strong hands were an adaptation for handling and processing food. As paleontologist Almudena Estalrrich, from the National Museum of Natural Sciences, points out, the muscle marks “indicate that he used them intensely, both to move and to obtain food. For example, he could have used a stone to break large seeds.”
Tools. This ability opens the door to the most important question: If he had such a dexterous and strong hand, did he make tools? For a long time, the manufacture of stone tools was considered a hallmark of the genre Homo. However, the KNM-ER 101000 demonstrates that P. boisei had the anatomical ability to do it, and now it remains to be seen if they actually did it.
Samar Syeda, a researcher at the American Museum of Natural History, believes that the human proportions suggest that it had some ability to make grips that would have allowed the use of tools. However, he cautiously adds that the morphology “primarily reflects locomotor use: a very strong type of grip.”
New scenario. This discovery now forces us to rethink the evolutionary panorama of the Pleistocene. Far from being a secondary and “unskillful” relative, the Paranthropus boisei was a right-handed hominid that coexisted with the first species of Homo.
The fossil KNM-ER 101000 proposes that while the lineage Homo was evolving towards greater dependence on lithic technology, Paranthropus he could have followed a different strategy, developing a powerful hand for the intensive exploitation of plant resources without the need for such refined technology (always in the context of that time).
In constant evolution. As Estalrrich concludes, the relevance of the discovery is immense, since this fossil not only lends a hand to an ancient relative, but also reminds us that the history of human evolution is constantly being rewritten, with each new discovery that we unearth.
Images | Wikipedia roger vaughan
In Xataka | Eating your neighbor is not illegal, technically. Unless you live in Idaho
GIPHY App Key not set. Please check settings